From nobody Fri Feb 21 16:07:19 2025 X-Original-To: freebsd-current@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Yzw4v2968z5nrY8; Fri, 21 Feb 2025 16:07:27 +0000 (UTC) (envelope-from barney@databus.com) Received: from pit.databus.com (tunnel234559-pt.tunnel.tserv4.nyc4.ipv6.he.net [IPv6:2001:470:1f06:80b::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4Yzw4t5Sp3z3kPK; Fri, 21 Feb 2025 16:07:26 +0000 (UTC) (envelope-from barney@databus.com) Authentication-Results: mx1.freebsd.org; none Received: by pit.databus.com (Postfix, from userid 202) id DE55E200F39; Fri, 21 Feb 2025 11:07:19 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=databus.com; s=20140217; t=1740154039; bh=5nGPI32pMbE5vpRVQ0rJwg08zpAe5J53zNSCFJgHwrE=; l=2349; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=eDOPCFjBi/k/1FwSYlXc0bYJqBm5HsMpkkLDpeYjtMMHf1GWHFbGTKNOsqNs0BVX1 I7AWAqPQZD4np6mazmQfuLlojX3veve9oeNTwxbxPZYAoOEucwhzvSiPjhsqg/H9Sq vGkIKtMuf+D6GpnUL3RdbKLcuQXM9A/ApU7qLLF+73n/2y5VlsbnvsevRaOAn1XKKq wAdr8i6OAoK83nF47+tYRUhRQQo9VUMnYAU+m/KgdNPUchtzeFQt/lTw+XZ43bifWL UzgX6vJ6irEUEDXB5OAQH66DJBZJicabz3GQ7K0+7NpIe5oRZ4fS32EZe/QSU8kzM/ lYTvBh8pekhuQ== Date: Fri, 21 Feb 2025 11:07:19 -0500 From: Barney Wolff To: A FreeBSD User Cc: FreeBSD CURRENT , freebsd-net@freebsd.org Subject: Re: rtadvd(8) How to IPv6 tokenize interface identifier Message-ID: References: <20250221075300.4466057d@thor.sb211.local> List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250221075300.4466057d@thor.sb211.local> X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US] X-Rspamd-Queue-Id: 4Yzw4t5Sp3z3kPK X-Spamd-Bar: ---- The problem is one of sequencing. A brute-force solution is not to start rtadvd until you get the prefix from upstream, then dynamically generate rtadvd.conf and start rtadvd. Ugly, but functional. On Fri, Feb 21, 2025 at 07:52:33AM +0100, A FreeBSD User wrote: > Hello, > > Linux (especially OpenWRT we use) knows about a concept named "IPv6 tokenized interface > identifier". The concept is self explanatory, a interface/router obtains a propagated prefix > and the concept allows the explicit definition of the host portion. > > I haven't managed to accomplish such a behaviour using FreeBSD's rtadvd(8) daemon. I guess > this task is subject of and performed through the rtadvd.conf(5) configuration file, but I > haven't managed yet to accomplish such a task (to speak simple: I'd like to have a router of a > subnet always at IPv6 Network PREFIX:0:0:0:1). > The only config tag I can imagine is responsible for what I'd like to achive is the "addr" tag > mentioned in rtadvd.conf(5), but whatever I fill this tag with - the desired effect is never > achived (i.e addr="::0.0.0.1"). My "FreeBSD homebrewn" router has several networks, attached > to vlan. Each interface is subject of an ULA prefix and an IPv6 prefix provided by our ISP. It > is possible to pin the ULA toward the desired address, like addr="fd50:c450::1", but then the > ISP provided prefix seems not to be set properly or is completely absent. Omitting "addr=" > provides the interface with ULA prefix and ISP prefix - but obviously with the randomly > generated 64bit host portion. > > Playing around with mutually suitable tags, like "pinfoflags", "raflags" or "rtflags" and > having probed almost every possible combination (with or without some sense), it seems > impossible to provide a) both ULA and ISP prefix pin the host portion to a desired 64bit > address, like "PREFIX::1". > > I do not exclude that I'm possibly incapable of comprehension the manpage (the language is and > the deeper semantics seem then to be hidden for me). So, if there is a clear expalanation how > to achive the desired, please point me towards it (thanks in advance!). > > Linux has this feature since a while and I can not believe that FreeBSD lacks such a feature. > > Thank you very much in advance, > > O. Hartmann > > > -- > > A FreeBSD user